Noise by bootleq

Play sounds when events happen, customizable.

Available events:

• Firefox startup
• Download start, completed, failed
• Back or Forward navigation
• Enter or leave fullscreen mode
• Clipboard copy, paste
• HTTP request completed, like 404 or 500 response
• Tab opened, closed, attached, pin, unpin, attention
• Tab groups created / moved / updated / closed
• Window opened / closed
• IME composition started

You have to add sound files on you own, please see options page after installed.

Hint: the Findbar wrapped event from legacy version of Noise can be replaced by accessibility.typeaheadfind.wrappedSoundURL config in Firefox 135.